Heavy Duty Industrial Filter The Pliotron HD filter is made with a unique three in one design perfectly suited to industrial filter applications. Our Pliotron 3-in-1 System: 1. The first layer is an aluminum mesh intake screen that prevents insects, lint and other large particles from accessing the interior of the filter. 2. The second layer of shredded polyethylene traps troublesome “fines” (sub visible particles that can cause long term damage to circuitry and machinery) and locks them in the depth of the media. 3. And the third layer is a spray bonded non- woven collector pad that stops and holds remaining airborne particles. The Pliotron HD also comes with the same reinforced steel hardware cloth and rust resistant, galvanized steel frame that comes with all our filters to ensure their durability and to simplify maintenance.